Mobile, QRP & Amplifiers

tweiss3

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So I have been thinking a lot about how I would like to take radio with me when the family goes on a trip or vacation. Currently my wife's car only has a UHF radio, and I would like to include VHF and HF.

I have to paths I could take to accomplish this, and I will probably head down both eventually. Which happens first will probably depend on what deal I can find.
1) Find a mobile all-mode and all-band radio (FT-857, IC-7000, etc.). This has a nice range of power options, but doesn't allow taking it in a backpack with ease.
2) Find a QRP all mode and all band radio (hoping to find someone letting one go after they get their shiny new IC-705).

In my searching for used radios, amplifiers keep popping up. Specifically inexpensive Chinese amplifiers. Now, I don't need tons of power, 20-50W would be plenty to supplement a QRP radio.
Q1) Are these cheap amplifiers permitted for use? I'm sure they aren't excellent at what they do, but is there some sort of certification needed to use an amplifier (Part 15?), or to stay away from?
Q2) I have seen some DIY amplifier kits. While I don't quite trust myself yet (its been a while since I have done tons of soldering) but it would be a fun project to build an amplifier. DIY is permitted, correct? For less than $20 shipped, I'm not sure I would trust the components or design.

And the final question, which would you pursue first?
 

AK9R

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I've noticed these made in China HF amplifiers. I would ask anyone selling such an amplifier for use in the U.S. if their product conforms with §97.315.

§97.315 Certification of external RF power amplifiers.
(a) Any external RF power amplifier (see §2.815 of the FCC Rules) manufactured or imported for use at an amateur radio station must be certificated for use in the amateur service in accordance with subpart J of part 2 of the FCC Rules. No amplifier capable of operation below 144 MHz may be constructed or modified by a non-amateur service licensee without a grant of certification from the FCC.

(b) The requirement of paragraph (a) does not apply if one or more of the following conditions are met:

(1) The amplifier is constructed or modified by an amateur radio operator for use at an amateur station.

(2) The amplifier was manufactured before April 28, 1978, and has been issued a marketing waiver by the FCC, or the amplifier was purchased before April 28, 1978, by an amateur radio operator for use at that operator's station.

(3) The amplifier is sold to an amateur radio operator or to a dealer, the amplifier is purchased in used condition by a dealer, or the amplifier is sold to an amateur radio operator for use at that operator's station.

(c) Any external RF power amplifier appearing in the Commission's database as certificated for use in the amateur service may be marketed for use in the amateur service.
 

tweiss3

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I've noticed these made in China HF amplifiers. I would ask anyone selling such an amplifier for use in the U.S. if their product conforms with §97.315.
That is what I was looking for. Likely the assembled units are not compliant, however, the DIY kits are because then it's my responsibility to make sure it operates correctly, doesn't splatter all over or cause interference?
 

prcguy

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RM Italy has a couple of amps with switchable low pass filters for the amateur bands that work fine with QRP rigs. I think you should consider more that 20-50w, that might be ok on a large base antenna but you need power to make up for inefficient mobile HF antennas.
 

WB9YBM

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Q1) Are these cheap amplifiers permitted for use? I'm sure they aren't excellent at what they do, but is there some sort of certification needed to use an amplifier (Part 15?), or to stay away from?

Q2) I have seen some DIY amplifier kits. While I don't quite trust myself yet (its been a while since I have done tons of soldering) but it would be a fun project to build an amplifier. DIY is permitted, correct? For less than $20 shipped, I'm not sure I would trust the components or design.

And the final question, which would you pursue first?
Some cheap amplifiers have either no, or limited, filtering on the output (that's how some CBers got caught--their signals were splattering all over the place, especially ion the first harmonic). Yes, DIY is permitted--even encouraged. That's what ham radio's all about. Unless you've got a lot of patience, QRP can get frustrating; even if band conditions are good enough to allow QRP signals to make it through, it's all too easy to get clobbered by the "big guns" out there. The only benefit I see here is a QRP radio is typically a bit smaller than "regular" radios so it (plus an amplifier) are easier to break down & store in luggage.
 

cognetic

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Hmmm... The FT-857 can be mounted on rails with a battery and made to fit in manpack style pack ( Yaesu FT 857d portable amateur ham radio battery packs and carrying systems ). I find the FT-857 with the ATAS120 a blast to operate mobile and the 857 can be removable for portable ops. Caveat, you need excellent ground between vehicle, radio, and antenna to operate the tuning appropriately. I keep the 857 on the portable zero mount and just add it to a fixed secondary mount in my vehicle boot attached to mobile antenna and 12v powerpole distribution.

That being said, I have several QRP, portable, and even remote operated station set-ups (including 817s, new IC-705 and Lab599 TX500 for QRP)... The set-ups vary depending on base camp, hike, marine, mobile, or recreational portable use configuration. I have a Tokyo Hi-Power amp and remote control, probably one of the best QRP add-on amps I have used. I find it takes to much room to carry the additional amp and prefer to use full power rig when wanting over 10w. I like the IC-7100 and RemoteRig set-up I have that allows ability to work HF and QTH local from anywhere with an internet connection.

The bigger issue with many of these set-ups is the antenna. For mobile, I found the 857 with ATAS120 one of my favorite set-ups for mixed mobile/portable use - once the ground issue is properly addressed (i.e. ground cable direct to antenna base and/or ground jumper to trunk or rear hatch), nothing has been easier!! I like the little tarheel, too, but too many extra components compared to the 857/ATAS120 combo. For portable, I'm using an Alex Loop, Chameleon MPAS 2.0, MPAS Lite, Alpha MIL Antenna with tripod, Par EndFed Antennas EFT-102040, buddipole, random wires, a W&S Walkabout, and several others - counterpoise length essential in many of these setups For mobile, in addition to the ATAS120, I have used the ICOM AH4 with AH2b with great success, as well. Fixed at home, I use HF vertical and several end-fed long wires....


Love this topic and happy to lend any of my knowledge from experience!!

- cognetic
 

tweiss3

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I've noticed these made in China HF amplifiers. I would ask anyone selling such an amplifier for use in the U.S. if their product conforms with §97.315.
After I saw this, I messaged about 6 different sellers asking the question. I got a response from 1 this morning, " yes, it is compliant with the US CFR ". I still have my doubts.

RM Italy has a couple of amps with switchable low pass filters for the amateur bands that work fine with QRP rigs. I think you should consider more that 20-50w, that might be ok on a large base antenna but you need power to make up for inefficient mobile HF antennas.
I appreciate the honesty. It points me to just buying a full power mobile rig. If in a real pinch, I will just toss my FT-450 in a case and take it with me. I was trying to fix two issues with one (getting VHF and HF in her car).

Some cheap amplifiers have either no, or limited, filtering on the output (that's how some CBers got caught--their signals were splattering all over the place, especially ion the first harmonic). Yes, DIY is permitted--even encouraged. That's what ham radio's all about.
I don't have much confidence in the kit I see (It has SMA connectors), but I may try it for fun and put it on someone's test equipment to really evaluate it.
Unless you've got a lot of patience, QRP can get frustrating; even if band conditions are good enough to allow QRP signals to make it through, it's all too easy to get clobbered by the "big guns" out there.
I have heard that about QRP, but some really like it, I figured I'd give it a shot. I could just turn my current rig down to 5W and see if I get too frustrated from the comfort of my home.
The only benefit I see here is a QRP radio is typically a bit smaller than "regular" radios so it (plus an amplifier) are easier to break down & store in luggage.
Honestly, a FT818 isn't much different in size than a FT857, so packing won't be all that different.

Hmmm... The FT-857 can be mounted on rails with a battery and made to fit in manpack style pack ( Yaesu FT 857d portable amateur ham radio battery packs and carrying systems ). I find the FT-857 with the ATAS120 a blast to operate mobile and the 857 can be removable for portable ops. Caveat, you need excellent ground between vehicle, radio, and antenna to operate the tuning appropriately. I keep the 857 on the portable zero mount and just add it to a fixed secondary mount in my vehicle boot attached to mobile antenna and 12v powerpole distribution.
I love that mount. I will probably buy one of those if I can find a 857.
That being said, I have several QRP, portable, and even remote operated station set-ups (including 817s, new IC-705 and Lab599 TX500 for QRP)... The set-ups vary depending on base camp, hike, marine, mobile, or recreational portable use configuration. I have a Tokyo Hi-Power amp and remote control, probably one of the best QRP add-on amps I have used. I find it takes to much room to carry the additional amp and prefer to use full power rig when wanting over 10w. I like the IC-7100 and RemoteRig set-up I have that allows ability to work HF and QTH local from anywhere with an internet connection.
I do have my rig setup to run remotely from my phone for SSB/AM/FM, and I can log into my desktop remotely to run FT8 or other modes, but it's not the same as operating in a field/on vacation.
The bigger issue with many of these set-ups is the antenna. For mobile, I found the 857 with ATAS120 one of my favorite set-ups for mixed mobile/portable use - once the ground issue is properly addressed (i.e. ground cable direct to antenna base and/or ground jumper to trunk or rear hatch), nothing has been easier!! I like the little tarheel, too, but too many extra components compared to the 857/ATAS120 combo. For portable, I'm using an Alex Loop, Chameleon MPAS 2.0, MPAS Lite, Alpha MIL Antenna with tripod, Par EndFed Antennas EFT-102040, buddipole, random wires, a W&S Walkabout, and several others - counterpoise length essential in many of these setups For mobile, in addition to the ATAS120, I have used the ICOM AH4 with AH2b with great success, as well. Fixed at home, I use HF vertical and several end-fed long wires....


Love this topic and happy to lend any of my knowledge from experience!!

- cognetic
I'm following the portable antenna thread (49:1 bauln) and think that is the way I will go for real portable. That will be the same as my base antenna at home (MyAntennas 8010).

I think I just need to find either a FT-857 or IC-7000 for an appropriate price. Right now, any I find are priced a few hundred more than a brand new IC-7100, which may not be as nice of a form, but is small enough to be mobile. If it comes down to it, that $700 hard limit will push me into a 7100.
 

AK9R

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After I saw this, I messaged about 6 different sellers asking the question. I got a response from 1 this morning, " yes, it is compliant with the US CFR ". I still have my doubts.
Ask them for the FCC ID number. Then, look up the number at the FCC Equipment Authorization search page (FCC OET Authorization Search). If the device referenced by the FCC ID doesn't match the device they are offering to sell, then there's a problem.
 

wa8pyr

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After I saw this, I messaged about 6 different sellers asking the question. I got a response from 1 this morning, " yes, it is compliant with the US CFR ". I still have my doubts.
The MX-P50M (widely available on eBay) does have filtering, hence the band switch on the front. I forget who it was, but someone on Youtube looked at the output of the MX-P50M he purchased with a spectrum analyzer, and it came out pretty well. It was well within required specs for spectral purity although one particular band was edging kind of close (but still within requirements).
 

prcguy

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The Yaesu FT-857 is not a bad radio for battery operation and it used to be popular for hiking, picnic table use, etc. I had one and used it a lot portable from batteries. The 857 is an ok radio, not great but just ok. I have a couple of Icom IC-7100s and would not use them portable from batteries. There are too many parts to lug around and they draw a lot of current on receive. Otherwise a great radio for mobile or base use.

I think I just need to find either a FT-857 or IC-7000 for an appropriate price. Right now, any I find are priced a few hundred more than a brand new IC-7100, which may not be as nice of a form, but is small enough to be mobile. If it comes down to it, that $700 hard limit will push me into a 7100.
 

tweiss3

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Ask them for the FCC ID number. Then, look up the number at the FCC Equipment Authorization search page (FCC OET Authorization Search). If the device referenced by the FCC ID doesn't match the device they are offering to sell, then there's a problem.
I asked, but I don't think it has one. Its the MX-P50M, which isn't a terrible design, but its using old recycled analog cell phone mofsets for the amplifier. I hear good things, but I think this idea is put on the shelf for another time.
The MX-P50M (widely available on eBay) does have filtering, hence the band switch on the front. I forget who it was, but someone on Youtube looked at the output of the MX-P50M he purchased with a spectrum analyzer, and it came out pretty well. It was well within required specs for spectral purity although one particular band was edging kind of close (but still within requirements).
I did some research on that one. It looks good, but for the price, let me put it together. and save a few bucks. Then at least it's compliant. Mixed reviews on the use of recycled components.
The Yaesu FT-857 is not a bad radio for battery operation and it used to be popular for hiking, picnic table use, etc. I had one and used it a lot portable from batteries. The 857 is an ok radio, not great but just ok. I have a couple of Icom IC-7100s and would not use them portable from batteries. There are too many parts to lug around and they draw a lot of current on receive. Otherwise a great radio for mobile or base use.
I heard that about the 7100, and to be honest, it's the last option, but it does set the hard cap on what I'd be willing to spend for a used transceiver, since I can pick one up today from DX and have it in hand brand new. Any other "mobile" all mode rigs I should be looking for? It must have 2m, would like it to have 70cm as well.
 

prcguy

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You want low receive current and the 857 is not bad there. I can't think of any other mobile to recommend, they are either too big or draw too much current. The 857 is not without problems, mine developed the dreaded LCD display stripes right after I sold it. It also has no effective transmit audio processing and about the best you can do is get the remote control mic which upgrades the mic element from a bad sounding dynamic type to an electret condenser with much better fidelity.

I bought my 857 in the late 90s for $400, put in a narrow SSB and CW mechanical filter and sold it about a year ago for $375, so they are not that expensive.

Update, I just remembered I took out the filters and sold them separately, so the stock radio went for $375.

Any other "mobile" all mode rigs I should be looking for? It must have 2m, would like it to have 70cm as well.
 

tweiss3

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You want low receive current and the 857 is not bad there. I can't think of any other mobile to recommend, they are either too big or draw too much current. The 857 is not without problems, mine developed the dreaded LCD display stripes right after I sold it. It also has no effective transmit audio processing and about the best you can do is get the remote control mic which upgrades the mic element from a bad sounding dynamic type to an electret condenser with much better fidelity.

I bought my 857 in the late 90s for $400, put in a narrow SSB and CW mechanical filter and sold it about a year ago for $375, so they are not that expensive.

Update, I just remembered I took out the filters and sold them separately, so the stock radio went for $375.
If I saw one for $375-450 right now, I'd be sending the money already. They are few and far between, usually starting at $750, which begs the question. Unfortunately, there isn't another option that is made new right now that I know of, which is a shame.
 

vagrant

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I use a compressor with my 817 & 897 for SSB. It works with the 857 as well. It is made by Funkamateur and it is the DYC-8x7. I think I paid $45 shipped from Germany. It is a little kit and easy to assemble. It definitely makes a difference. Still, an improved mic is the first step. I use a Heil headset for the serious jibber jabber.
 
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